Introduction: There are many paediatric neurological conditions that have a significant inflammatory component which have been demonstrated most notably by an increase in microglia populations. In a number of degenerative conditions, these changes are associated with a reduction in brain pH. Due to this potential overlap between the low pH and the increased brain microglia, we decided to
... [Show full abstract] investigate whether the increased populations of microglia in autistic tissue caused the reduced brain pH. Methods: Age, sex and cause of death matched prefrontal cortex sections were donated by the Institute of Psychiatry, King's College London. In vitro models were performed by stimulating murine neural tissue with inflammatory cytokines. Tissues were analysed using established histochemical techniques. Results: An ∼1 pH unit of difference between age, sex and cause of death matched tissue, and displayed a ±0.03 standard deviation within replicates. Staining with pH sensitive dyes suggested that the pH differences were located in lysosome-like structures in putative microglial cells. However, more significantly we demonstrated using a novel in vitro mouse model that we could induce such a pH change and subsequently reverse it by inactivation of the NF-κB/IKK signalling pathway. Conclusions: These results suggest that NF-κB represents a potential target for the therapeutic improvement of outcome in autism spectrum disorder. Furthermore, the identification of an association with pH changes opens scope for not only therapeutic interventions but the possibility of diagnostic imaging based on these preliminary results.